Phosphorus ureas

ABSTRACT

N-(Alkoxy-phosphinyloxy)- and N-(alkoxy-phosphinothioyloxy)-Nalkyl-N&#39;&#39;-substituted ureas of the formula   In this formula: R1 represents methyl or ethyl, R2 and R3 each independently represent a lower alkoxy or dialkylamino radical, X represents a lower alkyl, alkoxy, alkylthio or halogenoalkyl radical, halogen or the cyano group, Y represents oxygen or sulfur, and N REPRESENTS A NUMBER FROM 0 TO 3, WHICH ARE USEFUL AS HERBICIDES IN A METHOD FOR CONTROLLING WEEDS AND WILD GRASSES ARE DESCRIBED. Compositions containing such compounds are also described.

United States Patent 1191 Moser et al.

[ PHOSPHORUS UREAS [73] Assignee: Ciba-Geigy Corporation, Ardsley,

22 Filed: May 28,1970

21 Appl.No.: 41,638

[30] Foreign Application Priority Data June 6,1969 Switzerland ..8644/69 [52] US. Cl. ..260/938, 71/86, 7l/87, 260/553 A, 260/968 [51] Int. Cl. ..C07f 9/08, C07c 127/18, AOln 9/36 [58] Field of Search ..260/938, 553 A [56] Reierences Cited UNITED STATES PATENTS 3,393,253 7/1968 Wiesboeck ..260/938 3,384,683 5/ l 968 Schwarze ..260/938 Primary Examiner-Lewis Gotts Assistant ExaminerAnton H. Sutto Attorney-Karl F. Jorda and Frederick H. Rabin ABSTRACT N- (Alkoxy-phosphinyloxy} and N-(alkoxy-phosphinothioyloxy)-N-alkyl-N-substituted ureas of the formula In this formula;

R represents methyl or ethyl,

R and R each independently represent a lower alkoxy or dialkylamino radical,

X represents a loweralkyl, alkoxy, alkylthio or halogenoalkyl radical, halogen or the cyano group,

Y represents oxygen or sulfur, and

n represents a number from 0 to 3,

which are useful as herbicides in a method for controlling weeds and wild grasses are described. Compositions containing such compounds are also described.

3 Claims, No Drawings PHOSPHORUS UREAS The present invention concerns new urea compounds, process for the production thereof, herbicidal compositions, containing the new ureas as active ingredient and a method for the control of weeds. and wild grasses employing the new active substances or compositions containing them.

The novel urea compounds correspond to the Formula I:

In this formula:

R represents methyl or ethyl,

R and R each independently represent a lower alkoxy or dialkyl-amino radical,

X represents a lower alkyl, alkoxy, alkylthio or halogeno-alkyl radical, halogen or the cyano group,

Y represents oxygen or sulfur, and

n represents a number from O to 3.

In Formula I, lower alkyl radicals X mean straight or branched-chain radicals having one to four carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tertbutyl. Such alkyl radicals likewise form the alkyl part of lower alkoxy, alkylthio, halogenoalkyl or dialkylamino radicals X, R, and R Halogenoalkyl radicals means lower lakyl radicals substituted by fluorine, chlorine and/or bromine, in particular the trifluoromethyl radical. Halogen means fluorine, chlorine, bromine, and iodine.

The novel urea compounds of the Formula I are produced according to the invention by reacting a hydroxy urea of the Formula II:

NHe-N (X),, OH (II) with a halide of the Formula III:

R2 Hal-Il| Y Ra (III) in the presence of a base and a solvent or diluent which is inert towards the reaction components. In Formula II and III, X, Y, R R R and n have the meanings given for Formula I, Hal means chlorine or bromine. The reaction temperatures lie between and 80C. Tertiary amines such as trialkylamines and pyridine bases, inorganic bases such as hydroxides and carbonates of alkali metals and alkaline earth metals are employed as bases. Examples of solvents or diluents suitable for the process according to the invention are aliphatic and aromatic compounds such as dioxane, tetrahydrofuran, N,N-dialkylated amides, ketones, nitriles, alcohols such as alkanols, water and mixtures or organic solvents with water such as alcohol/water mixtures or chloroform/water mixtures.

The novel urea compounds of Formula I, in which R represents a dialkylamino radical and R represents an alkoxy radical, are obtained by a'modification of the process according to the invention by reacting a hydroxyurea compound of Formula II with a dihalide of Formula IV:

Hui ii 1v wherein I-Ial represents chlorine or bromine,

R represents a dialkylamino group, and

Y represents oxygen or sulfur, in an alkanol of the formula V R OH v wherein R is a lower alkyl radical in the presence of an acidbinding agent.

The known hydroxy-ureas of Formula II, employed as starting materials, can be obtained by known methods by reacting the appropriately substituted phenylisocyanates with appropriately substituted hydroxylamines.

The novel urea compounds of Formula I are obtained in the process according to the invention in good yields and in good purity. Some of the compounds are crystalline, others are oils; they are readily soluble in the usual solvents, sparingly soluble in water and various carbohydrates.

The novel ureas of Formula I possess excellent herbicidal properties and can be employed for the control of mono and dicotyledoneous weeds and wild grasses. In concentrations of from 8 to 20 kg/ha the new ureas have a total herbicidal effect, in concentrations of from 0.5 to 8 kg/ha they have a selective herbicidal effect. The action of these substances includes the types of weeds which are difficult to control as well as the deep rooted types, e.g. leguminous and umbelliferous plants. They can be applied with equal success before (preemergence) and after emergence (postemergence) of the plants. Thus field weeds, such as types of millet (Panicum sp.), types of mustard (Sinapis sp.), types of goose foot (Chenopodiaceae), field foxtail (Alopecurus sp.) and other types of foxtail, e.g. Amaranthus sp., grasses, e.g. Lolium sp., compositae, e.g. Taraxacum sp., types of chamomile (matricaria sp.) can be destroyed or their growth can be hindered without damaging cultivated plants.

The following examples illustrate the production of the new compounds of Formula I according to the invention. Where not stated otherwise, temperatures are expressed in degrees Centigrade.

EXAMPLE 1 To a solution of g of N'-(3,4-dichlorophenyl)-N- methyl-N-hydroxy-urea and 127 ml of triethylamine in 2 liters of benzene, there are slowly added dropwise with stirring at l0l5, 172 of chloro 0,0-diethyl thiophosphate, dissolved in 250 ml of benzene. The reaction mixture is stirred for 12 hours at room temperature and then heated for 2 hours at 50 to 60. After cooling, the precipitate is re-moved by filtration and the filtrate is concentrated in vacuum. The residual yellow oil is boiled up with petroleum ether, purified with animal charcoal and decanted. The N-(diethoxyphosphinothioyloxy)-N-methyl-N-(3,4- dichlorophenyl)-urea has a melting point of 40 to 42.

EXAMPLE 2 temperature 19 g of choloro 0,0-diethyl phosphate are EXAMPLE 3 To a solution of 23.5 g. of N'-(3,4-dichlorophenyl)- N-methyl-N-hydroxy-urea in 250 ml of ethanol, there are slowly added dropwise with stirring at OlOC, 18.33 ml of 6 N sodium hydroxide solution and then 17.82 g of (dimethylamido)-phosphoryl dichloride. Stirring is continued for half an hour and 16.6 ml more of 6 N sodium hydroxide solution are added dropwise at 5-10. Then the reaction mixture is stirred at room temperature and, after attaining a neutral reaction and a negative result in the FeCl test, poured into ice water. The resulting precipitate is separated, washed with ice water and dried. After recrystallization from ethanol, the obtained N-(ethoxy-dimethylaminophosphinyloxy )-N-methyl-N'-( 3 ,4-dichlorophenyl)-urea has a melting point of 96-98.

EXAMPLE 4 First 16.7 ml of 6N sodium hydroxide solution and then 14.5 g of chloro, 0,0-dimethyl phosphate are added dropwise at 25 with stirring to a suspension of 24.5 g of N'-(4-bromophenyl)-N-methyl-N-hydroxyurea in 300 ml of methylen chlorde and 150 ml of water. Stirring is continued for 1 hour at room temperature. After the reaction has become neutral and a negative result is obtained in the FeCl test, the organic phase is separated, washed with water and dried over sodium sulfate. The crystalline residue which remains after evaporation of the methylene chloride is recrystallized from benzene. The N-(dimethoxy-phosphinyloxy)-N-methyl-N'-(4-bromophenyl)-urea obtained has a melting point of 135137.

The compounds of Formula 1 listed in the following table were produced by the methods described in the above examples starting from the appropriate amounts of hydroxyphenyl-urea;:

TABLE 1 Example No. Compound Physical data 5 N-(diethoxy-phosphinyloxy )-N-methyl-N 4- bromophenyl)-urea m.p. 85-87 6 N-(diethoxy-phosphinyloxy)-N-methy1-N 2 chlorophenyl)-urea m.p. 48-50 7 N-(diethoxy-phosphinyloxy )-N-methyl-N 3- methyl-phenyl)-urea m.p. 4446 8 N-(diethoxy-phosphinyloxy )-N-methyl-N 2- methyl-pheny1)-urea m.p. 42-46 9 N-[bis-(dimethylamino)-ph0sphinyl0Xy]-N- methy1-N-pheny1-urea n =1.5226 10 N-[ bis-(dimethylamino )-phosphinyloxy I-N- methyl-N 3 ,4-dichlorophenyl)-urea m.p. 84-8 6 l 1 N-(dimethoxy-phosphinothioyloxy )-N- methyl-N'-phenyl-urea m.p. -61 12 N-( dimethoxy-phosphinothioyloxy )-N- methyl-N'-(4-bromophenyl)-urea m.p. 58"60 1 3 N-(dimethoxy-phosphinothioyloxy)-N- methy1-N'-(4-iodophenyl)-urea m.p. 57-59 14 N-( dimethoxy-phosphinothioyloxy)-N- methy1-N'-(3,4-dichlorophenyl)-urea m.p. -77 15 N-( dimethoxy-phosphinothioyloxy )-N- methy1-N-(4methylthio-phenyl)-urea m.p. 35-37 16 N-(diethoxy-phosphinothioyloxy)-N-methyl- 17 N-(diethoxy-phosphinothioyloxy)-N-methyl N'-(3-chlorophenyl)-urea m.p. 5052 18 N-(diethoxy-phosphinothioyloxy)-N-methy1- N-(4-chlorophenyl)-urea n ,,"=1 .5 439 19 N-(diethoxy-phosphinothioyloxy )-N-methyl- N'-(4-fluorophenyl)-urea m.p. 3435 20 N-(diethoxy-phosphinothioyloxy )-N-methy1- N'-(4-bromophenyl)-urea m.p. 42-45 21 N-(diethoxy-phosphinothioyloxy)-N-methyl- N'-(4-iodophenyl)-urea m.p. 49-5 1 22 N-( diethoxy-phosphinothioyloxy )-N-methyl- N-(2-chlorophenyl)-urea n =1.5417 23 N-(diethoxy-phosphinothioyloxy )-N-methyl- N-(2-methyl-pheny1)-urea n,,=1.5345 25 N-( diethoxy-phosphinothioyloxy-N-methyl- N-(3methyl-phenyl)-urea m.p. 38-40 26 N-( diethoxy-ph0sphinothioyloxy-N-methyl- N'-(4-methy1-phenyl)-urea n,,*=1.5334 27 N-(diethoxy-phosphinothioyloxy )-N-methyl- N-(2-methoxy-phenyl)-urea n =1.5345 28 N-(diethoxy-phosphinothioyloxy )-N-methyl- N '-(4-ethoxy-phenyl)-urea n =1.5322 29 N-(diethoxy-phospinothioyloxy)-N-methyl- N'-(4-methylthio-phenyl)-urea m.p. 44-46 30 N-(diethoxy-phosphinothioyloxy )-N-methyl- N'-(4-cyano-phenyl)-urea n,,1.55 10 3 1 N-(diethoxy-phosphinothioyloxy )-N-ethyl- N'-(3,4dichlorophenyl)-urea m.p. 40-42 3 2 N-( dimethoxy-phosphinyloxy )-N-methyl-N (3-iodophenyl)-urea 3 3 N-dimethoxy-phosphinothioyloxy )-N-methyliodophenyl)-urea 3 5 N-(diethoxy-phosphinothioyloxy )-N-methyl- N'-( 3-iodophenyl)-urea 3 6 N-( dimethoxy-phosphinyloxy )-N-rnethyl-N (3-chloro-4-methoxy-phenyl)-urea m.p. 128130 3 7 N-( dimethoxy-phosphinothioyloxy )-N- methyl-N 3-chloro-4-methoxyphenyl urea m.p. -102" 3 8 N-(diethoxy-phosphinyloxy )-N-methyl-N 3- chloro-4-methoxy-phenyl)-urea m.p. 82-84 39 N-(diethoxy-phosphinothioyloxy(-N-methyl- N 3-chloro-4-methoxy-phenyl)-urea m.p. 70-7 2 40 N-dimethoxy-phosphinyloxy)-N-methyl-N (3-chloro-4-methyl-phenyl)-urea m.p. 89-91' 41 N-(dimethoxy-phosphinothioyloxy )-N- methy1-N'-( 3-chloro-4-methyl-phenyl)- urea 66-67 42 N-(diethoXy-phosphinyloxy )-N-methyl-N 3- chloro-4-methyl-phenyl)-urea m.p. 86-8 8 43 N-( diethoxy-phosphinothioyloxy )-N-methy1 N 3-chloro-4-methyl-phenyl)-urea m.p. 5 65 8 44 N-(dimethoxy-phosphinyloxy)-N-methyl-N (3-methyl-4-bromo phenyl)-urea m.p. l l0-l 13 45 N-( dimethoxy-phosphinothioyloxy )-N- methyl-N'-( 3methyl-4-bromo-phenyl)-urean.p. 69-7 0 46 N-(diethoxy-phosphinyloxy)-N-methyl-N 3- methyl-4-bromo-phenyl)-urea m.p. 98-100 47 N-(diethoxy-phosphinothioyloxy )-N-methyl- N 3-methyl-4-bromo-phenyl)-urea The herbicidal action of the novel urea compounds is illustrated by the following tests:

1. Preemergence test with test plants grown from seed The active substance, in the form of a 10 percent powder concentrate, is mixed, in a concentration of 1 g of active ingredient per square meter of soil, into garden soil. Seed trays are filled with a 1 cm-layer of this prepared soil. The following test plants:

oats (Avena sativa),

mustard (Sinapis arvensis),

Italian Ray grass (Lolium multiflorum),

tomato (Solanum lycopersicum millet (Setaria italica), are sown in the seed trays and kept in daylight in a greenhouse at 20 to 24C and 70 percent relative humidity. The test plants were evaluated after 20 days and the evaluation is expressed according to the following scale:

10 plants undamaged control plants dead 9l intermediate degrees of damage.

The 10% powder concentrate has the following composition:

10 parts of active ingredient, 0.6 part of dibutylnaphthalenesulfonic acid-sodium salt, 1 part of naphthalenesulfonic acid/phenolsulfonic acid/formaldehyde condensation product (3:2: 1 10 parts of sodium aluminum silicate and 78.4 parts of kaolin.

TABLE II compound Italian Example oats mustard Raygrass tomato millet No.

1 4 0 0 2 0 0 0 4 o 0 0 0 0 5 0 0 O 0 0 7 0 0 0 0 0 8 l O l 0 2 9 0 0 0 0 0 10 0 0 0 0 0 ll 0 O O 0 0 12 0 0 0 0 0 l3 0 O 0 0 0 l4 0 O 0 0 0 l6 0 0 0 0 0 17 0 0 0 0 0 1s 0 0 0 o 0 19 0 0 0 0 0 20 0 0 0 0 0 21 0 0 0 0 1 23 0 1 0 0 2 25 0 0 0 0 1 26 1 0 1 2 2 29 0 0 o 2 1 2. Herbicidal action when the active sustances are applied after emergence of the test plants As test plants, oats (Avena saliva) and mustard (Sinapis alba) are grown in plastic pots. In the 2 to 4- leaf stage the plants are treated with a 2 percent aqueous emulsion of the active ingredient (obtained from a 25 percent emulsifiable concentrate) in a concentration corresponding to 5 kg per hectare and then kept in dayling at 25 28 and 40 50 percent relative humidity. After 7 days the test is evaluated according to the following scale:

10 plants undamaged (control) 9-l intermediate degrees of damage 0 plants dead.

The emulsifiable concentrate has the following composition: 25 parts of active ingredient, 32.5 parts of lsophorone (3 ,5 ,5-trimethyl-2-cyclohexen- 1 -one), 32.5 parts of methyl ethyl ketone, 10 parts of a composite emulsifier consisting of a mixture of nonylphenol polyoxyethlene and calcium dodecylbenzene sulfonate.

TABLE 111 a. Compounds according to the invention:

Compound Example No. l l

mustard b. Compounds according to South African Patent No. 67/4170:

Mus-

Oats tard 4:1 0 C ONHCHa CHa-N (I:

O C ON(O1I3) 2 OCONHCHZOH;

C Ha-N 3. Postem ergence test with weeds grown from seed The test plants, wheat (cultivated plant), Chenopodium album, Sinapis arvensis, Polygonum convolvulus, Polygonum persicaria, Atriplex, millet, and Capsella bursa pastoris, are sown in seed trays. In the four-leaf stage the plants are sprayed with a 2 percent aqueous emulsion. Then the plants are kept at 25-28 and 40-50 percent relative humidity under daylight.

The test is evaluated after 8 days (A) and after 18 days (B), according to the following scale of l0:

10 plants undamaged control 0 plants dead 9-l intermediate degrees of damage.

TABLE I\' Herbicidal cll'cct ou- Concentration Chonop. Siunpis Polyg. con. Polyg. per. Atriplox Millet Capsclla in Active substance kg/ha. A B A B A B A I A B A B A B N-[dictlwxy-phosphinthi0yl-0xy1-N-methyl- N-(3, i-dichlorophenyl) 1. 0 O O 0 b 1 3 l 0 0 n 1 4 0 urea. l 3 0 U 0 0 l O 3 2 0 0 1 1 1 0 5 0 0 0 0 0 0 2 1 0 0 1 1 0 2 4. Effect on planted weeds when applied after emergence of the plants in the field:

The follwing weeds were shown in a prepared seedbed: Sinapis alba, Amaranthus spec., Galium aparine, Taraxacum officinalis and Lolium multiflora. When the plants were 5 to cm high (depending on the variety), they are sprayed with an aqueous emulsion of the active substance. 18 days after treatment, the effect is evaluated according to the following logarithmic index:

l 100 percent effective on the planted weeds 4 90 percent effective on the planted weeds 9 no effect.

The aqueous emulsion was obtained by diluting with water a percent emulsifiable concentrate having the following composition: 25 parts of active ingredient, 5 parts of a composite emulsifier consisting of nonylphenolopolyethylene and calcium dodecylbenzol sulfonate, 67.5 parts of xylene and 2.5 parts of epichlorohydrin.

acid and salts 2-chloro-4,6-bis-(ethylamino )-s-triazine, 2-chloro-4,-ethylamino-6-isopropylamino-s-triazine, 2-methoxy-4,6-bis-( isopropylamino)-s-triazine, 2-diethylamino-4-isopropylacetamido-6-methoxystriazine, 2-isopropylamino-4-methoxypropylamino-6- methylthio-s-triazine, 2-methylthio-4,6-bis-(isopropylamino)-s-triazine, 2-methylthio-4,6-bis-(ethylamino)-s-triazine, 2-methylthio-4-ethylamino-6-isopropylamino-striazine, 2-methoxy-4-ethylamino-6-isopropylamino-striazine,

TAB LE v Amaran- Sinapis thus Galium Taraxa- Lollrwn Active substance Kg./ha. alba. spez. aparine cum 01f. mullzfl 1 4 4 1 N -idiethoxy-phosphinothioyl- 2 2 1 1 1 4 oxy]-N-m ethyl-N (3,4- 3 2 1 1 1 2 dichlorophenyD-urea. 4 2 1 1 1 2 5 2 1 1 1 2 (2-methyl-4-chlorophenoxy)-acetic acid and salts and esters thereof,

2-(2,4,5-trichlorophenoxy)-propionic acid and salts and esters thereof,

2-(2,4,5-trichlorophenoxy)-ethyl-2,2-

dichloropropionate,

4-(2,4-dichlorophenoxy )-butyric acid and salts and esters thereof,

4-( 2-methyl-4-chlorophenoxy)-butyric acid and salts and esters thereof,

2,3,6-trichlorobenzyloxypropanol,

4-amino-3,5,6-trichloropicolinic acid,

N-cyclooctyl-N,N-dimethyl-urea,

3-phenyl-l l -dimethyl-urea,

3-(4'-chlorophenyl)-l I -dimethyl-urea,

3-( 3'-trifluoromethylphenyl)- l l -dimethyl-urea,

3-( 3' ,4-dichlorophenyl)-1,l-dimethyl urea,

3-(3',4'-dichlorophenyl)-l-n-butyl-l-methyl-urea,

3-( 3' ,4-dichlorophenyl)-l l ,3-trimethyl-urea,

3-(3,4'-dichlorophenyl)-1,l-diethyl-urea,

3-( 4' -chlorophenyl)- l -methoxyl -methyl-urea,

3-( 3' ,4-dichlorophenyl l -methoxyl -methyl-urea,

3-( 4' -brom0phenyl l -methoxy- 1 -methyl-urea,

3-( 3 ,4-dichlorophenyl)-3-methoxy-1,l-dimethylurea,

3-( 4-chlorophenoxyphenyl)- l l -dimethylurea,

N,N-di-(n-propyl)-S-ethyl-thiocarbamate,

N,N-di-(n-propyl)-S-n-propyl-thiocarbamate,

N-ethyl-N-(n-butyl)-S-n-propyl-thiocarbamate, N-phenyl-O-isopropyl-carbamate, N-(m-chlorophenyl)-O-isopropyl-carbamate,

N-( m-chlorophenyl )-O-4-chloro-butyn-( 2 )-yl-carbamate,

N-( 3 ,4 -dichlorophenyl )-O-methyl-carbam ate.

The production of herbicidal compositions according to the invention is performed in a known manner by intimate mixing and grinding of active substances of the general Formula I together with suitable carriers, optionally with the addition of dispersing agents or solvents, which are inert towards the active substances. The active substances can be used and applied as dusts, scattering agents, granulates, coated granulates, impregnated granulates, homogeneous granulates, wettable powders, pastes, emulsions, solutions or aerosols.

For the production of solid preparations (dusts, scattering agents, granulates) the active ingredients are mixed with solid carriers. The particle size of the carriers is from about 0.075 to 0.2 mm for dusts, and 0.2 mm or more for granulates. The concentration of active ingredient in the solid preparations is usually 0.5 to 90 percent, preferably 1.0 to 80 percent. These mixtures can also contain additives which stabilize the active ingredient and/or substances which are non-ionic,

or anionically or cationically active, which substances, for example, improve the adhesion of the active ingredients on plants or parts of plants (adhesives and agglutinants) and/or ensure a better wettability (wetting agents) and dispersibility (dispersing agents).

Water-dispersible concentrates of the active substance, wettable powders, pastes and emulsion concentrates, are compositions which can be diluted with water to any desired concentration. They consist of active substance, carrier, optionally additives for stabilizing the active substance, surface-active substances and anti-foaming agents, and optionally solvents. The concentration of active substance in these preparations is from 5 to 80 percent. The wettable powders and pastes are obtained by mixing and grinding the active substances with dispersing agents and pulverulent carriers in suitable equipment until the products are homogeneous. In some cases it is advantageous to use mixtures of different carriers. The anti-foaming agents may, for example, be silicones. The active substances are so mixed, ground, sieved and classified with the abovementioned additives that in the wettable powders the solid fraction does not exceed a particle size of 0.02 to 0.04 and in pastes does not exceed 0.003 mm. Dispersing agents, organic solvents and water are used for the preparation of emulsion concentrates and pastes. The solvents must be practically odorless, nonphytotoxic, inert towards the active substances and not easily combustible.

Furthermore, the compositions according to the invention may be applied in the form of solutions. For this purpose, one or more of the active substances of the general Formula [is or are dissolved in suitable organic solvents, mixtures of solvents, or water. The concentration of the active substances contained in the solutions should be in the range of to 30 percent. Other biocidal active substances or agents can be admixed with the compositions described according to the invention. Thus, in addition to the said compounds of the general Formula I and other herbicides, the new compositions may contain, for example, insecticides, fungicides, bactericides, fungistatic and bacteriostatic substances or nematocides in order to broaden the range of action.

The compositions according to the invention may also contain plant fertilizers, trace elements, etc.

Preparations containing the new ureas are described.

below. Parts are expressed by weight.

GRANULATE polyethylene glycol and cetyl poly glycol ether are added. The resulting solution is sprayed onto kaolin and the acetone is then evaporated in vacuo.

WE'ITABLE POWDER The following components are used for the prepara tion of a. 50%, b. 25% and c. 10% wettable powders:

a. 50 parts of N-[diethoxy-phosphinothioyl-oxy]-N- methyl-N'-(3,4-dichlorophenyl)-urea, 5 parts of sodium dibutylnaphthyl sulfonate,

3 parts of naphthalene sulfonic acid/phenol sulfonic acid/formaldehyde condensation product (3:2:1 20 parts of kaolin, 22 parts of Champagne chalk; b. 25 parts of N-[diethoxy-phosphinothioyl-oxy]-N- methyl-N'-(4-chlorophenyl)-urea, 5 parte of the sodium salt of oleylmethyl tauride, 2.5 parts of naphthalene sulfonic acid/formaldehyde condensation product, 0.5 part of carboxymethyl cellulose 5 parts of neutral potassium aluminium silicate, 62 parts of kaolin; c. 10 parts of N-[diethoxy-phosphinyl-oxy]-N- methyl-N-4-bromophenyl)-urea, 3 parts of mixture of sodium salts of saturated fatty alcohol sulfates, 5 parts of naphthalene sulfonic acid/formaldehyde condensation product, 82 parts of kaolin.

The given active ingredient is absorbed onto the corresponding carriers (kaolin and chalk) and then mixed and ground. Wettable powders having excellent wettability and suspensibiltiy are obtained. By dilution with water, suspensions of any desired concentration of the active ingredients can be obtained from such wettable powders. Such suspensions are suitable for the control of weeds and wild grasses incultivated plantations.

PASTE The following ingredients are used for the preparation of a 45 percent paste:

45 parts of N-[diethoxy-phosphinothioyl-oxy]-N- The active ingredient is intimately mixed and ground in suitable equipment with the additives. A paste is obtained which can be diluted with water to prepare suspensions of any desired concentration. Theses suspensions are suitable for the treatment of vegetable plantations.

EMULSION CONCENTRATE wherein R represents methyl or ethyl,

R and R each independently represent lower alkoxy or di-lower alkylamino,

X represents lower alkyl, lower alkoxy, lower alkylthio, halogeno loweralkyl, halogen or cyano,

Y represents oxygen or sulfur, and

n represents an integer from 0 to 3.

2. A compound as defined in claim 1, which is N-. (diethoxyphosphinothioyloxy )-N-methyl-N 3 ,4- dichlorophenyl)-urea.

3. A compound as defined in claim 1, which is N- (diethoxyphosphinyloxy)-N-methyl-N-( 4-bromophenyl )-urea. 

2. A compound as defined in claim 1, which is N-(diethoxyphosphinothioyloxy)-N-methyl-N''-(3,4-dichlorophenyl)-urea.
 3. A compound as defined in claim 1, which is N-(diethoxyphosphinyloxy)-N-methyl-N''-(4-bromophenyl)-urea. 